Repair and Strengthening of Bell Tower of a Church in Glyfada

After the installation of the scaffoldings around the bell tower, a rigorous inspection of the concrete bearing elements was carried out. Several damages were detected along the full height of the tower. A technical report was prepared, including the damage assessment and the proposed interventions along with the corresponding budget.

After the acceptance of the proposal, works started:

  • Removal of the damaged concrete.
  • Cleaning and protection of the steel reinforcement by applying corrosion inhibitors.
  • Rehabilitation of the concrete elements with cement repair mortars.
  • Strengthening of the columns and beams of the upper part of the bell tower with carbon fiber reinforced polymers (CFRP).

Strengthening of Listed Building on Hydra Island

The mansion consists of two buildings and built approximately a century ago. It has a marvelous view on Hydra port and sea. During the last decades it was abandoned and the deterioration through time was very obvious. The new owner decided to fully rehabilitate and strengthen the stone masonry walls of the two buildings so as to extend their service life for many more decades though aging and future earthquakes. The stone masonry walls were not covered at the exterior by any plaster, so the rehabilitation scheme was not allowed to include interventions that could alter the facades of the buildings. The order of the works that took place was as follows: local repairs and rehabilitation of the stone masonry walls, grouting hoses installation and rigorous pointing of the whole surface of the walls, strengthening of the stone masonry walls with an internal perimeter foundation and shotcrete jacketing and by injecting cement grout (of a proper three component cement grout composition) through the whole walls volume and with the construction of a new perimeter reinforced concrete beam at the crest of the walls on which the new wooden roof was based.

Strengthening of Stone Masonry Building

The bearing stone masonry walls of the building were fully strengthened. The plaster was removed; the loose parts of the stone masonry walls were reconstructed and repaired by replacing the stones; the cracks were repaired and walls surfaces were repointed where necessary. Subsequently, perimeter foundation was constructed and both sides of the stone walls were jacketed with shotcrete at their full height. In order to strengthen the crest of the walls a reinforced concrete perimeter beam was constructed and was followed by the construction of the concrete roof slab.

Strengthening of 2nd High School of Athens

The static analysis of the project called for the preservation of the facades, the removal of the rest of the building and the construction of a new interior reinforced concrete bearing structure that would be connected with the stone masonry bearing surrounding walls.

The bearing structure of the building consists of stone masonry walls and slabs made of structural wood or reinforced concrete. Before the removal of the interior structure, extensive works for the homogenization of the exterior walls, which needed to be preserved, took place. The works for pointing (4,000m2) and stone replacement preceded. The homogenization was achieved by injecting cement grout (100,000Lt) of the proper composition, compatible with the masonry connection mortar. The injection complex was composed of a turbulence vortex mixer, a mixing unit and a pump with pressure control device, as required for registered historic buildings. The quality control included constant measurement of the fluidity and bleeding of the mixture as well as testing of prismatic specimens to calculate the bearing capacity of the grout in bending and compression. After the completion of the grout injections, a temporary steel framework was constructed to support the perimeter walls, the old interior structure was removed and the construction of the new reinforced concrete started. For the integral connection of the perimeter walls to the new concrete structure, 6,000 Φ14 – 80cm dowels were used.